Protector-removing device



June 21, 1960 R. s.' TAYLOR, JR

PROTECTOR-REMOVING DEVICE 4 Sheets-Sheet 1 Original Filed Sept. 18, 1950 INVENTOR.

June 21; 1960 R. G. TAYLOR, JR

PROTECTOR-REMOVING DEVICE Original Filed Sept. 18, 1950 4 Sheets-Sheet 2 imam/v0 6: 72% 0E, dz,

JNVENTOR.

firm/avers.

June 21, 1960 R. e. TAYLOR, JR

PROTECTOR-REMOVING DEVICE Original Filed Sept. 18, 1950 4 Sheets-Sheet 3 fim Ma/va 6: 774 102, dz,

JNVENTOR.

Arm/avers.

June 21, 1960 R. G; TAYLOR, JR 2,941,283

PROTECTORREMOVING DEVICE Original Filed Sept. 18, 1950 4 Sheets-Sheet 4 IZG 82 Pay/valve 6: 774m 02, J4,

INVENTOR.

7.26. a. BY l fi United States Patent PROTECTOR-REMQVIN G DEVICE Raymond G. Taylor, Jr., Santa Monica, Calif., assignor, by mesne assignments, to Borg-Warner Corporation, Chicago, 111., a corporation of Illinois Continuation of application Ser. No. 185,468, Sept. 18, 1330.6 This application Mar. 29, 1954, Ser. No.

15 Claims. (Cl. 29-236) This invention relates generally to well drilling equip ment and more particularly to a device useful in apparatus for removing protectors from drill pipe.

' In the drilling of wells by the rotary method, one of the ever-present problems is that of wear on the drill pipe and on the inner wall of the casing installed in the well, such wear being occasioned by likely contact between said drill pipe and casing. Hence, it is common practice in the rotary drilling art to apply to the string of drill pipe numerous resilient protectors. Such protectors are usually composed of rubber or rubber-like material and are spaced at proper intervals upon the string of drill pipe to prevent contact of the drill pipe and par: ticularly of the tool joints thereof with the casing.

These protectors ordinarily comprise cylinders which when installed thereon encompass the pipe. In order that they may tightly grip the pipe and thereby prevent slippage, the protectors are molded with their internal diameters smaller than the external diameter of the pipe and are thus difiicult to remove from the drill pipe over the tool joint without damage when such removal is desirable. After a protector-equipped string of drill pipe has been used in drilling a well the protectors are usually but slightly worn and therefore re-usable in the drilling of another well. If such pipe string is to be used shortly thereafter to drill a second well, the protectors mounted thereon may safely remain on the pipe. If, however, such pipe is not to be used for some time it is preferable that the protectors be removed therefrom and placed in protective storage. Such storage will avoid damage to the protectors resulting from exposure to the elements" while under tension upon the pipe, the pipe usually being stored in open unprotected racks when not in use.

' Heretofore, several devices have been suggested for removing protectors from drill pipe. Generally, such devices comprise a base member adapted to be secured to the floor of a derrick and having upwardly extending Thus, any failure of the hoisting mechanism or miscalcu lation or carelessness of the operator thereof can easily.

result in serious injury to the crew members.

In a copending application for United States Letters Patent, entitled Apparatus for Removing Protectors from Pipe, Serial No. 185,466, filed Sept. 18, 1950, by De Mont G. Miller and Rodney R. Wood, there is, however, shown a power apparatus for removing protectors from pipe, which apparatus may be operated independent of the derrick and away therefrom, and which apparatus thus avoids the above difiiculties. Generally such apparatus consists of a pipe-engaging means abuttable against the extremity of the drill pipe and tension members connected to the pipe-engaging means, which tension members are adaptable for connection to protector-engageable means. The pipe-engaging means consists of a.

' relatively movable plunger-cylinder assembly, which en tector on over the end of the pipe.

ables an element to which the tension members are connected to be moved relatively away from the pipe end to causethe protector-engageable means to push the pro- The protector-engageable means, as disclosed in such application, consists of hook-shaped dogs having hooks or lips which engage the protector by grasping the same between the pipe surface and the inner diameter of the protector. Such type of protector-engageable means, and indeed others of.

' similar structure, have proven generally satisfactory for ing operation more difiicult.

arms. The upper end of the arms includes hooks or other means for engaging a pipe-mounted protector. For the removal operation the pipe is suspended in the derrick adjacent the device and the protector-engaging means are 7 connected to the upper end of a protector to be removed from the pipe. The pipe is then elevated whereby the protector is pulled off over the bottom end thereof. Such devices have proven fairly satisfactory, but inasmuch as they require the use of the derrick equipment and the drilling crew, the usual drilling operations must necessarily 'be'delayed during the protector-removing process and thus'considerable added expense occasioned. Furthermore, a considerable number of protectors are ordinarily will beapparent from the'following detailed description;

protector-removing operations but certain disadvantages occur in their use. The certain disadvantages occur in their use particularly where are involved unusually stubborn protectors, or where are involved drill pipe tool joints having such conformity as to present shoulders ex-v tending radially outwardly from the surface of the drill pipe in such degree as to render the passage of the protector thereover unusually difficult.

form distribution of abutting force about the periphery of the end of the protector and increases the tendency'to split the protector at one of the hooks. increase the tendency of one or more of the up on the pipe and generally Further, they Consequently, it is the principal object of the present invention to provide a protector-engageable device which may be used'with apparatus for removing protectors from pipe and which will uniformly distribute the protector abutting forces at the end of the protector.

It is a further object of the present invention to provide,

such a protector engageable device which will reduce the possibility of tearing or otherwise damaging a protector] during the removal operation.

Yet another object of the invention is to provide such a device which may be simply and quickly applied to the protector.

A further object of the invention is to provide protectorengageable apparatus which will not tend to hang up on the pipe during the removal operation.

' Another object of the invention is to provide such a device capable of applying a uniformly distributed force to the protector, but at the same time capable of being" positively held in close pipe-encompassing position where by to engage the protector with a minimum danger of pinching portions of said protector against the pipe or of riding over the protector and thus failing to remove thesame.

Yet another of the objects of this invention is to pie-1', vide such a proteotor-engageable device capable of'outaj respect to the pipewhereby to ac-f Patented June 21, 1960.

Here the presence 'of hooks and the like fails to present an optimum unihooksto hang render the protector-remjov-' 3 taken in conjunction with the accompanying drawings Whiil'li Figure 1 is a top view of a protector-engageable device embodying the present invention, operatively connected. toiprotectorremoving apparatus andin position toremove. aphid-mountedprotector.

Figure .2 is. a side elevational View of. the device of Figure 1.

Figure 3 is a front elevational view of theld'evic'e of Figures 1' and Ztaken' on the line 3-3 of'FigureZ from. which view the protector itselfhas been omitted.

Figure 4 is a cross-sectional view of the device taken on the line 4'-4 ofFig'ure 2';

Figure 5 is a partial longitudi'nal'*sectional view taken onithe' line 5--5 of Figure 3.

Figure 6 is another partial longitudinal sectional viewtaken" on the line 66 of Figure 3'.

' Figure 7 is afragment'ary frontelevational' view of the protector-engage'able device shown in the preceding figures' as. modified for use in removing protectors fromsmaller size pipe.

Figure 8' is a partial longitudinal section of the device of Figure'7' taken on the line -88'of Figure 7.

Figure 9 is a partial longitudinal section of the device of Fi'gure' 7" taken on the'line 9-9 of Figure 7.

With reference to the drawings, it will be seen that the invention in its general aspect comprises apair of support. arms 20' and 2x2, pivotally joined at one oftheir ends and! integrally carrying a pair of abutment members 24' and Z'liadaipted'to be clamped" about the pipe. 28' adjacent the protector 30 to be removed and. to abut the end of said protector. The arms 20 and 22 arecapable offconne'otion to a protector-removing device generally designated 32, which device serves to draw the protectorengagea'ble device of the instant invention along the pipe 28, so that it may remove the protector 30 over extremity.- 3*? of the pipe 28. The support arms 20 and '22 and hence the. abutment members 24 and 26 may be latched" posi; tively about the pipe 2 8' in close. conformity thereto by. means of the releasable limit means. or latch 36,. but. due. to the pivotal interconnection between.- the said arms, upon release of said latch 36, said arms, and consequently the abutment members, are capable of transversemovement outwardly of the pipe to permit the device to pass over the pipe tool joint 38. The aforesaid trans verse movement is resiliently constrained by thespring assembly 40..

The particular proteotorsremoving. device 3-2. shown. operating. in conjunction. with the instant invention isv set forth in detail in the aforementioned applicationof Miller and. Wood but. may be described. here briefly as. follows. A plunger. 42, extending from a cylinder 44,.is either. of such conformation or mounts an adapter 46 as topermit abutment of the pipe extremity 34. The cylinder 441 through fluid pressureintroduced through the fittings- 48 and 50'may be caused to slide outwardly from. the said pipe on the plunger 42 and carries a yoke 52, saidyoke 52 havingan arcuate passageway 54 through. which passes a chain 56' connected by the slotted hooks 58 and 60: to the device of the instant invention. Thus, when. fluid. presvsure is admitted to the cylinder 44 to cause outward movement. thereof withrespect to the plunger. 42. and the pipe. 28, thechain 56 draws the support arms '20.and.22. and the abutment members 24 and 26 along the: pipe 28. Such abutment members engage the protector30, forcing said protector along the pipe 28 over the. tool joint 38 and beyond the pipe extremity 34'. If. desired; the relea'sable latch 36 may be utilized to prevent any outward. {transverse movement of the arms 20 and. '22,. and hence the abutment members 24 and 26,.untilthe tool joint 38 is. reached; whereupon release of said latch will permit the resiliently restrained outward movement of. said armsand abutment members to accommodate the abutment members to the diameter of the tool joint. Thus, inthe-protector removing operation surface contact against the protector whereby to provide uniform force distribution is assured, the likelihood of tearing the protector minimized, positive latching of the support arms and abutment members against outward transverse movement made available whereby to minimize possible pinching of the protector against the pipe, and resiliently constrained outward movement of the support arms and abutment members permitted to accommodate passage of the device over the tool joint.

Referring more particularly to the details of construction of the invention, the support arms 20 and. 22 are preferably of tubular construction and include slots 62 at one of their extremities wherein the slotted hooks 58 and '60 may be rigidly secured, as by welding. The ends of the arms 20 and 22 may be beveled as at 64 adjacent the slotted hooks so as to facilitate the interconnecting and the disconnecting of the chain 56 with respect to said hooks.

The opposite ends of the support arms 20 and 22 are.

rigidly secured, as by welding, to a pair of pivot plates 661 and 68, respectively. Pivot plate 68 includes a pair of'lugs 70, and pivot plate 66 includes a cooperating lug 72, whichv lugs are provided with aligned bores adapted tov receive a pivot pin 74. This pivot pin is secured by a. cotter pin 76 extending through the lug 72. Adjacent the. lower lug 70' and also carried by the pin 74 is a guide. tongue 78 which, as will be seen hereinafter, is to prevent any possible hang up of the pivot assembly on thev tool joint 38 during the protector-removing operation. It will be noted that when the device is in position to remove adapted to straddle the pipe 28 with the pivot assembly disposed atop the pipe, and the slotted books 58 and.60.

spaced substantially equidistant from opposite sides. of the pipe. The abutment members 24 and 26 are as shown rigidly secured, as by welding, to one of the support arms 20 and 22, respectively, at such angle that they will be disposed transversely to the pipe 28 when the protectorengageable device is in position to remove a protector. A reinforcing gusset 80 may be provided for each abutment member to strengthen the attachment thereof. to its respective support arm. Each abutment member is seen. to comprise broadly a generally triangular base plate. 82 ibrmed'with a pipe-receiving recess 84 and an arm-receiv ing recess 86. The pipe-receiving recess 84 should be of a. radius whereby its edges will be closely spaced to, but not incontact with, the periphery of the pipe 28, as shown in. Figure 3. A pusher pad 88 of rubber or rubber-like material is mounted on each base plate adjacent the pipereceiving recess and in overlapping relation thereto, preferably with its inner edge lightly contactingthepe riphery of the pipe. Each pusher pad 88 is preferably secured to the. face of its respective base plate 3 2'by means of; a mounting plate 90 having integral attachment pins 92 adapted to be extended through bores M formed in the-pusher. pads. The pins 92 are retained in the bores. 96in. the base plate 82 by lock washers 98 and nuts 100. These pins may include a portion of enlarged diameter 102, whereby there is formed an abutment surface 104. adapted to shoulder. upon the face of each. base plate to prevent excessive deformation of the pusher pads 88 through overly tight threading of the nuts 100. It should be understood that it is not essential that the pusher pads 88 be formed of'rubber or rubber-like material. Such.

pads may instead be formed of other material having abutment member 26 and a mounting lug 118 spaced from the spacer 116 by a bridging element 120. The lug 118 may be rigidly secured to the support arm 22, as by Welding. A pivot pin 122, supported within aligned bores formed in the base plate 82, the spacer i116 and mounting lug 118, respectively, is shown extending through the bore 124 in the support bracket 110 so as to pivotally support the latch bolt 108, the said pivot pin 122 being secured by a cotter pin in the usual manner. A cradle 126, having a trough 128, is rigidly secured, as by welding, to the support arm 20 and to the other base plate 82 of the abutment member 24. Such cradle '126 is adapted to receive the threaded end of the latch bolt 108, so as to restrict the maximum transverse separation between the abutment members 24 and 26 by the engagement of the side surface 130 of the said cradle with the adjusting hut 112. Such separation may be varied by. manipulation of the two nuts 112 and 114 with respect to the threaded end of the latch bolt 108.

The spring assembly 40, which is adapted for operation during release of the latch 36, comprises a horizontally disposed bolt 132 slidably carried inbores134 formed. in lugs 136 rigidly secured. to the upper portion of the base plate 82 of the abutment members 24 and 26. A sleeve 138, disposed on the bolt between the two lugs 136, serves to maintain a minimum transverse clearance between the abutment members.- Two springs 140 and 142 are positioned each between one of. the lugs 136 and washers144 and 146, respectively, which washers are, in turn, respectively, -backed by an adjusting nut 148, held by-a lock nut 150 secured to the threaded end of the bolt, and by the bolt head 152. To adjust the spring pressure, the bolt head 152 may be held against rotation while the two nuts 148 and 150 are screwed or unscrewed on the bolt. The bores 134 are of suflicient diameter to permit the bolt 132 to slide freely therein, whereby each spring 140 and 142 will be tightened or loosened to the same degree. a

In the operation of the above-described apparatus, it is first necessary to apply the protector-engageable device to the pipe. For this purpose, the latch bolt 108 is raised from the cradle trough 128 permitting resiliently constrained transverse separation of the abutment members 24 and 26. The operator may force these members apart as by sharply urging the device downwardly toward the pipe whereby the inclined lower surfaces 154 of the base plates 82 will strike the sides of the pipe and 'thus cam the members apart sufiiciently to allow the device to assume the operating position shown in the drawings. The latch bolt 108 may then be disposed in locking position with its threaded end in the cradle trough 128, the adjusting nut 112 of the latch being so adjusted that the inner edges of the pusher pads 88 substantially correspond to the periphery of the pipe. With this arrangement, any likelihood that the pusher pads may be pulled over the protector during the initial loosening of the protector issubstantially eliminated. It will, of course, be appreciated 3 that in the case of an easily loosened protector, the latcl1- ing operation may be dispensed with and the spring assembly 40 depended upon to prevent over-riding of the protector. It is recommended that a lubricant, such as soap solution, be applied to that portion of the pipe-and tool joint over which the protector will be moved.

Connection may be then made between the aforesaid device and the protector-removing device 32 by connecting the chain 56 to the slotted hooks 58 and 60. It is recommended in this step that one of the end links of the chain 56 be connected to a hook and the chain pulled through the arcuate passageway 54 and hooked at an intermediate link on the other side of the device to avoid slack in the said chain. Fluid pressure may now be admitted to the cylinder 44 to cause it to move axially away from the pipe extremity 34. Such axial movement will be transferred to the yoke 52, the chain 56 and, in turn, to the protector-engageable device. This device,

through engagement of the pusher pads 88 with the end' as an appreciable area of each pusher pad is in contact with the end of the protector during this operation, the

unit bearing pressure acting against the protector is com-' para-tively-small whereby there is less danger of either pad tearing the protector.

In the event that the releasable latch has been used in latched position as the protector rides onto the tool joint 38 and .as the abutment members 24 and 26 approach the tool joint, it will be necessary to release said latch to permit the abutment members to separate sutficiently to allow the pusher pads 88 to follow the contour of the tool joint. The springs and 142 should be so adjusted as to exert sufficient closing force upon the abutment members to make certain that the pusherpads will remain closely spaced to the periphery of the tool joint as the protector is urged alongand over the joint.

Ifeach protector to be removed is positioned adjacent the tool joint of the pipe at approximately the same-distance from the end of the pipe as shown in Figure 1, it will not be necessary to alter the distance between the protector-engageable device and the yoke 52. Frequently, however, a protector will have slipped along the pipe to a position further removed from its end. Accordingly, the chain 56 should be of suflicient length to reach these axially displaced protectors. Ordinarily, a single stroke of the protector-removing device 32 will not be sufficient to completely remove the protector, and the chain 56 will have to be disconnected and reconnected to take up slack therein. It has been found most convenient when removing such protectors to leave one end of the chain connected to one of the slotted books 60 and to detach the chain from the other slotted hook 58 to take up slack, aftenwhich the chain may be reconnected for another stroke of the said protector-removing device.

This procedure may be repeated as many times as required in order to remove the protector from the pipe.

It should be particularly pointed out that occasionally a protector will be encountered which will require considerable initial removal force in order to loosen its grip; upon the pipe, although after such a protector is loos ened a much lesser force would be suflicient tomove it"- ofl the pipe. The provision of the releasable latch 36 to positively lock the abutment members 24 and 26' against transverse separation eliminates the .possibility' of the pusher pads 88 overriding the end of the protector-1 during the application of a necessarily strong initial re moving force. However, as pointed out hereinbefore, the

latch may be dispensed with'entirely and the cons-training force of the spring assembly 40' relied upon to prevent:

undue transverse separation of the abutment members" during the protector-removing operation. This of;

course, limits the effectiveness of the device to the more normally adhering protector, although if the springs 140' and 142 be tightened suificiently, even ztight protectors:

may be removed in the absence of the. latch.. On the other hand, such expedient would make application of:

the device exceedingly diflicult due to the necessity of: camming open the abutment members 24 and 26 wheninstalling the apparatus. It will also be appreciated that for the removal of protectors and the like from pipe hav-' ing no section of increased diameter, such as the tool- 40 may be dispensed withjoint 38, the spring assembly and the releasable latch 36 relied upon'solely.

Referring now to Figures 7, 8 and 9, there is shown a manner whereby the aforedescribed protector-engage-'; able device may be adapted for use with smallersize In this modification an adapter element 158;.

pipe 156.

is interposed between each pusher pad '88 and basev plate 82. Each adapter element 158 is formed with a pipe;

receiving recess 160 having a radius such that its edgefwill,

be closely spaced to, but not contactwith, theper-iphery,

of the pipe 156. The adapter elements are formed with boresl62. to receive attachment pins 92.01? the mount-ing. plate 9.0 and serve to back up the. pusher pads 88. which, however,.{wi1l. preferably slightly overlap the adapters. to lightly engage the periphery of the pipe.

It willbe apparent. to those skilled in. the art that. variousother modifications and. changes. may be. made without departing tromthe essence ofthe' invention, and it is intended to cover herein allsuch. modifications and changes as are within the. true scope. and spirit of the appended claims.

This. application is a continuation of my application Serial No. 185,468, filed September 18, 1950,. now abandoned.

I claim:

l.v In. ameans for. removing protectors from pipes having. enlarged sections, a protector engaging; apparatus. comprising. a plurality of. abutment members-having surfaces for engaging a protector and. having arcuate edges defining, an aperture for receiving and encompassing. a: pipe,.means to one, side of said aperturev connecting said abutment. members together. for movement relative to one another, said means including a spring assembly attached to. said abutment members for forcing saidv members together, said abutment members defining. a radial access opening to said aperture diametrically opposite to said spring assembly, said access opening always being unobstructed, said abutment membersbeing transversely separable against the urgingv ofsaid springassernbly to allow a pipe to pass through said. access opening and to allow said abutment members tov ride. transversely out and. over any enlarged sections in apipe encompassed thereby.

2. A device as set out in claim 1 wherein. said spring. assembly. includes a bore defining. member mounted. on. each abutment member, a bar slidably disposed in said bores and having spring. stop means at opposite ends thereof, and springsmounted on opposite ends of said bar and compressed between said bore defining. members and said spring stop means.

3. A device asset out in. claim 2 wherein at least one of said. spring. stop means is. adjustable to vary the effective-length of said. bar to vary the constraint exercised. by saidsprings.

4. A device as set out in claim 1 including a releasable limit means interconnecting said abutment members independently ofsaid spring assembly to provide a stop against. said. transverse separation.

5. A: device. as set out in claim 4 wherein said limit meansis. located adjacent said spring assembly on. the

diametrically opposite side of said aperture from: said.

access opening.

6; A deviceas set out in. claim 1 wherein each. of said abutment. members. comprises a planar portion having:

edges which constitute said. aperture defining edges, said aperture. being of. such a diameter that said edges termi-v nate in; close proximity to a: pipe encompassed by said abutment memfbers,-andr-ubberlike deformable pads carried by said. planar. portions. and having. bearing surfaces lying: in a. plane transverse. to a. pipe. in said aperture,

saidpads. overlapping said edges of. said planar'portions and having edge-surfaces engageable with. a pipein said aperture.

7. In a: means. for removing protectors from pipes having enlarged sections, a protector engaging apparatus comprising; aplurality of abutmcntmem-bers having surfaces for engaging a protector and having arcuate edges. defining an aperture for receiving and encompassing a pipe, means connecting said abutment members together for movement relative to one another, said means includ-' inga plurality of connecting members each secured respectively to one of said abutment members, means movably interconnecting'said connecting members to permit relative movement of said abutment members toward and away-from each other, a spring assembly'attached to said abutmentmembers to" one side'of' said' aperture for fore 8. A device as set out in claim 7 including a releasable limit means interconnecting said abutment members independently of said spring assembly to provide a stop against said transverse separation, said limit means being located on the diametrically opposite side of the said aperture from said access opening.

9-. In a means for removing protectors from pipeshaving enlarged sections, a protector engaging apparatus comprising; a pair of abutment members having surfaces for engaging a protector and having arcuate edges.

defining'an aperture for receiving and for encompassing a pipe, a pair of support arms, pivotmeans joining said support. arms adjacent one pair of ends thereof, said.

support arms having their free ends attached to said abutment members on opposite sides of said aperture to permit relative movement of said abutment members towards and away from one another, means adjacent said pivot means for causing the latter to slidably ride over apipe which passes through said aperture, a spring assembly attached to said abutment members and being situated to one side of said aperture to normally urge said members together, said abutment members defining a radial access opening to said aperture diametrically opposite to said spring assembly, said access opening always being unobstructed, said abutment members being transversely separable against the urging of said spring assembly to allow a pipe to pass through said access opening and to allow said abutment members to ride transversely out and over any enlarged sections in a pipe encompassed thereby.

10. A device as set out in claim 9 wherein said spring assembly includes a bore defining member mounted on each abutment member, a bar slidably dis-posed in said bores and having spring stop means at opposite ends thereof, and springs mounted on opposite ends of said bar and compressed between said bore defining members and said spring stop means.

11. A device as set out in claim 9 including releasable limit means interconnecting said abutment members independently of said spring assembly to provide a stop against said transverse separation.

12. A device as set out in claim 11 wherein said limit means is located adjacent said spring assembly on the diametrically opposite side of said aperture from said access opening.

13. In a means for removing protectors from pipes having enlarged sections, a protector engaging apparatus comprising; a pair of abutment members having surfaces for engaging a' protector and having arcuate edges defining an aperture for receiving and for encompassing a pipe, boredefining members mounted on said abutment members and defining bores in axial alignment and to one side of said aperture, a' bar slidably disposed in said bores, stop means on opposite ends of said =bar', springs mounted onsaid bar' at opposite ends thereof between said bore defining members and said stop means to urge said abutment members together, said abutment members defining an unobstructed radial access opening to said aperture diametrically'opposite to said bar, and releasable' limit means interconnecting said abutment mem bers on the sameside ofsaid aperture as" said bar, said limit" means co'mprising'a bridging member h'avin'g'one endpivotally affixed to one abutment member andhaving its free end slidably and removably engaged with a catch means afiiire'd' to said other abutment member to permit said abutment members to move toward each other but to limit their movement away from one another.

14. A device as set out in claim 13 wherein said separating movement of said abutment members is limited by an adjustable stop on said free end of said bridging member.

15. Apparatus for engaging a protector for removal of said protector from a pipe comprising: a pair of pivotally joined transversely separable support arms adapted to be slida'bly mounted on said pipe with each arm disposed at one side of said pipe, said support arms being connectible to a means for inducing axial movement thereof with respect to said pipe; abutment members carried by said support arms and movable therewith transversely of said pipe during removal of said protector therefrom to override protuberances on said pipe, said abutment members being adapted to assume a substantially encompassing relation about said pipe and having surfaces transverse to said pipe and engageable Withsaid protector; a releasable latch adapted to interconnect said 10 support arms to provide a positive stop against said transverse separation; and a spring assembly connecting said abutment members to resiliently constrain said transverse separation.

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